I have a 86 6 port 13b with a street-ported engine ....i just got a downdraft weber set up and i do not know what jets to put in it please help!!

 

What size venturi do you have in the carb? The venturies are replaceable on the Weber, and the size will affect the jets that you need.

 

You should be able to see the size in the top edge of the venturi. I'm assuming this is a 48IDA, you should have somewhere around a 38 to 42mm venturi in there depending on what it was sized for.

 

Your right it is a 48IDA and i reads 37 when u look way down into the barrels

 

I have a feeling that your IDA is off the shelf item. 37 is too small for street use. You have go up to at least a 40, 70 idle, 250+ needle/seat, 150 air and 200+ main plus total 3 progression holes per barrel. Play with jets and work your way up

 

thanx bud i will try it out

 

Venturis where hard to find a few months back we ended up going with some Gene Berg made units.